A conventional technique for forwarding computer messages to any one of a number of final destinations is to use a pattern of bits to identify the destination of a particular message, and then walk the pattern bits through a Patricia tree structure of a direct table and, if necessary, through one or more Pattern Search Control Blocks (PSCB's). One such technique is shown and claimed in application Ser. No. 10/448,528 filed May 30, 2003, entitled “Multi-Bit Patricia Tress”. In this application, the PSCB's are multibit, thus reducing the latency time. However, this problems in updating the Patricia tree. The present invention describes a technique for updating the Patricia tree by inserting and deleting leaves without interrupting the functioning of the Patricia tree.